When the hot water dies, decisions come fast. Here are the system types compared, the brands worth quoting and the resources that get it replaced right.
⟳ Updated August 2026A hot water system fails on average once a decade, which means most owners buy one in a hurry, knowing nothing. This guide fixes that: the system types compared honestly, the major brands ranked, and the services that surround a smooth replacement.
The companion guide site: system comparisons, sizing help and replacement advice, the homework that turns a panic purchase into an informed one.
Hot water and drainage share the same tradespeople. Drains Australia covers the drainage half, worth bundling into the same call-out when the plumber is booked.
All Suburbs lists home services by coverage area, the quick route to installers and related trades that actually service your suburb.
Rheem is the Australian market's dominant hot water name, with electric, gas, solar and heat pump ranges and parts availability everywhere plumbers work.
Rinnai leads the continuous-flow gas segment: compact wall-mounted units delivering endless hot water, strong where gas is connected and space is tight.
Dux manufactures hot water systems in Australia, with competitive tank and heat pump ranges that quote well against the bigger names.
Bosch brings European engineering to gas continuous flow and heat pump ranges, a quality alternative worth including in any three-quote process.
Storage tanks typically last around a decade, sometimes more with sacrificial anode replacement; continuous flow units often go longer with servicing. A tank past its warranty period is living on borrowed time.
Heat pumps lead on running cost in most climates, followed by solar with boosting, then gas, then conventional electric tanks. Purchase price runs roughly in the reverse order, which is why the decision is a horizon calculation.
Roughly, a couple manages with smaller tanks or continuous flow; a family of four wants a mid-size tank in the hundreds of litres or a well-sized continuous unit; larger households need bigger again. Simultaneous showers and bathtubs push sizing up.
Like-for-like is fastest and cheapest on install day; upgrading to heat pump or solar costs more upfront and repays through running costs and rebates. If the old system limped for months, use the warning period to plan the upgrade.
A straightforward like-for-like electric or gas swap sits in the low thousands installed, continuous flow similar, with heat pumps and solar above that before rebates. Access difficulties, relocation and switchboard work add to any quote.
Australian federal and state schemes routinely discount heat pumps and solar hot water, sometimes dramatically. Ask every quoting installer to state the after-rebate price, because rebate paperwork is part of their job.
No, plumbing and energy connections legally require licensed trades in Australia and most markets, and DIY connections void warranties and insurance. Your job is choosing the system and the installer, not holding the spanner.
Rusty or discoloured hot water, water pooling at the tank base, rumbling or banging, and hot water that runs out faster than it used to. Any of these is the cue to get quotes before the cold-shower morning.
If gas is already connected, continuous flow gas remains a strong performer; if not, running a new gas line rarely makes sense against a heat pump. Many households replacing gas tanks now weigh the all-electric path.
Same-day or next-day for common like-for-like swaps in metro areas, assuming stock; type changes take longer for wiring, gas or plumbing modifications. That speed gap is why failure-day decisions default to like-for-like.
For tanks, releasing the pressure relief valve periodically and replacing the sacrificial anode around mid-life; for continuous flow, periodic servicing. Ten minutes of maintenance a year routinely adds years of service.
Three quotes, same system class, itemised: unit, installation, removal of the old system, valves and compliance. The cheapest headline often omits removal or valve replacement, and the gap appears on invoice day.
Hot water systems choose their moment: a cold morning, a full house, the week the budget was already spoken for. And panic is expensive, the failure-day buyer accepts the first quote, the default system and the nearest installer, routinely overpaying for an under-considered decade of running costs.
The antidote is making the decision before the failure forces it. Here is the sequence.
The type decision, tank versus continuous, electric versus gas versus heat pump versus solar, is a ten-year running-cost calculation that deserves an unhurried evening, not a cold-shower morning. Use the comparison resources ranked above, factor rebates on the efficient options, and write the decision down. A household that already knows its next system converts failure day into a logistics exercise.
Systems rarely die unannounced: discoloured hot water, base moisture, tank noises and shrinking capacity are the gauge reading low. Any sign appearing in a system past its warranty years is the trigger to gather quotes at leisure, and replacing a month early costs nothing while replacing a day late costs comfort, laundry and premium call-out rates.
Quotes only compare when scope matches: same system class, installation, old-system removal, valves and compliance items all itemised. Rebate-eligible systems should be quoted after rebate. An hour of quote discipline typically saves hundreds, and the installer who itemises cleanly is usually the one who installs cleanly.
Call-out costs make solo jobs expensive, so failure day is also opportunity day: the slow drain, the dripping valve and the gutter downpipe all cost less fixed during the same visit. The directory and drainage resources above exist for exactly this bundling, and a fifteen-minute site walk with the plumber often pays for itself immediately.
Type decided early, warnings heeded, quotes disciplined, jobs bundled. That is the entire difference between a hot water emergency and a hot water errand.